The present invention relates to a multi-layered thermoplastic container opened by partially peeling back a multi-layered top heat-sealed to the edge of said container and comprising, from bottom to top, a tear-off, simple or complex, internal sheet permanently heat-sealed on the edge of said container, a simple or complex intermediate sheet provided with an opening for access or a curved line for incision or weakening for opening and firmly adhering to said internal sheet at least outside the zone defined by said access opening or at least partially closed curved incision line, as well as a simple or complex outer sheet adhering, on the one hand, in peelable manner, to the intermediate sheet outside said zone defined by the access opening or the curved incision line made in this intermediate sheet and, on the other hand, in firm and non-peelable manner, either directly to a part of the internal sheet traversing said access opening, or to the intermediate sheet inside the zone defined by said incision line, said container further comprising a peeling tab in order to facilitate grip of the outer sheet on the edge of said recipient thermoformed from a multi-layered thermoplastic band.
In the case of known containers of this type, the internal sheet of the multi-layered top is hermetically heat-sealed on the layer of thermoplastic material of same nature of the edge of the container with complex wall, with the result that it is not easy, if not difficult, and even impossible to grip the edge of said top in order to peel the outer sheet and reveal the opening giving access to the container.
In order to facilitate grip of the outer sheet, and the beginning of the peeling thereof, it has already been proposed (FR 2 503 036) to make in a corner of the edge of the container provided with its top, from the lower face of said edge, a notch for weakening making it possible to break, by folding, said corner up to the outer sheet and to peel the latter from the intermediate sheet of said top. This modus operandi does not make it possible easily to provide the start of peeling at any point whatsoever of the edge of the container and, in addition, the operation of partial cutout or incision for making the notch can only be effected separately from the cutout of the containers and independently thereof.
Another known proposition for making a start of peeling (FR 2 551 031) consists in forming on an edge of the top between the intermediate sheet and the outer sheet thereof, a zone of non-adherence by a special treatment of non-adherence of one or the other of these two sheets. This treatment of non-adherence is expensive and the desired effects thereof are often destroyed during heat-sealing of the top on the edge of the container.
The edge of the top is crimped by the effect of cutout punches, in particular with the sharp profile necessary for the multi-layers.